The present invention relates to securely transferring user authentication information from a first computer to one or more other computers to allow the user to interact with the other computers without necessarily having to explicitly identify himself thereto. More particularly, the present invention includes the use of cryptographically assured cookies in a distributed computer environment.
The widespread proliferation of links among networked computers allows users to effortlessly navigate from one computer to another. For example, in the Internet environment, users can obtain publicly available information by following links from any computer to any other computer, in an anonymous fashion, without previously knowing of, being known to, or having an account on, the other computer. However, to access certain secure areas of a business""s web site, or to carry out an electronic transaction (e.g., a purchase), the user must typically be known to and/or have an account on, that web site. Today, the user must perform a separate sign on and/or authentication process with each such web site, i.e., the fact that the user has authenticated himself to a first site can not be easily transferred to an unrelated second site.
The data structures known as xe2x80x9ccookiesxe2x80x9d have conventionally served as a general mechanism by which server computers can store and retrieve information on a client computer. For example, a conventional cookie allows a server computer to customize its web site for a particular client computer by reading the preferences information stored in a conventional cookie in the client computer. Typically, the server computer would be a computer running a business""s web site and the client computer would be a user""s computer running a web-browser program. Conventional cookies are also used to authenticate registered users of a particular web site without requiring them to sign in again every time they access that same web site. Additional information regarding conventional cookies can be found at http://www.illuminatus.com/cookie.fcgi.
However, conventional cookies can not be used for transferring authentication from one site to another site for two reasons. First, the degree of security provided by conventional cookie authentication is inadequate for many types of transactions, even in the single site (same site) case. For example, banks offering on-line banking services on the Internet often require sophisticated security measures for the storage of highly confidential information that are not contemplated by conventional cookies.
Second
A browser will not give up it""s cookie data to any server except the one that set it. If your browser went around spewing all it""s cookies to every site you hit this would be a security risk and would make cookies worthless. (emphasis in the originalxe2x80x94see http://www.illuminatus.com/cookie.fcgi)
Therefore, the conventional mechanism of cookies does not allow for transferring authentication. Instead, the user must perform a separate authentication process with each business web site, even if the user has already gone through a reliable, secure authentication process at a previous business web site. This multiple sign on process is redundant, inefficient, and cumbersome for the user. As the amount of business being done on the Internet increases, or as specialization leads to the outsourcing to third parties of certain parts of an electronic transaction such as bill payment, this multiple sign on process will become increasingly cumbersome for the user.
All of the foregoing shows that there is a need to develop methods and systems for securely transferring user authentication information from a first computer to a second computer to allow the user to seamlessly interact with the second computer without necessarily re-authenticating himself thereto.
The present invention overcomes the limitations and disadvantages of the prior art by providing a method for securely transferring user authentication information from a first computer to a second computer to allow the user to seamlessly interact with the second computer without necessarily re-authenticating himself thereto. Cryptographically assured data structures are created to enable a single sign on and/or authentication method. Thus, if a second computer trusts the methods used by a first computer to authenticate a user, then the second computer can use a cryptographically assured cookie created by the first computer to authenticate the user, without requiring the user to perform an explicit authentication step at the second computer.
This system has numerous advantageous over the prior art. The user does not necessarily have to go through an explicit authentication step at each business web site (although, for added security, such could also be used). In addition, the user does not necessarily have to remember authentication information such as user names and user passwords for each business web site. The transfer of user authentication information can be done easily, seamlessly, and securely, thus facilitating transactions in which the user either does not know the second computer, or would be inconvenienced by having to separately authenticate himself thereto. The first and second computers could be, without limitation, virtually any type of content service provider on the Internet.
In an exemplary embodiment of the invention particularly well suited to Internet applications, a cryptographically assured cookie is made by creating a cryptographically assured voucher at the first computer, and embedding the voucher into a cookie for transmission to the user""s computer and hence to the second computer. Although conventional cookies and cryptography are both known in the prior art, the combination of these two components to create a new type of cryptographically assured cookie is not known or suggested by the prior art. Indeed, the prior art teaches away from cookies as used in the present invention.
For example, as discussed in the Background, the prior art teaches away from the present invention by prohibiting cookies created by one server (i.e., a first computer) from being disclosed to or read by another server (i.e., a second computer). More particularly, the prior art teaches that this would create a security risk and make cookies worthless. These prior art teachings concerning conventional cookies are diametrically opposed to the present invention, which teaches how to have cookies created by one computer be read by other computers without creating a security risk.
The foregoing and other embodiments and aspects of the present invention will become apparent to those skilled in the art in view of the subsequent detailed description of he invention taken together with the appended claims and the accompanying figures.